Biodegradation of Trisodium Nitrilotriacetate in a Model Aerated Sewage Lagoon

Abstract

The effect of temperature on the biodegradation of trisodium nitrilotriacetate (Na₃NTA) in a model aerated sewage lagoon was investigated. The percent breakdown of incoming NA₃NTA at 15, 5, and 0.5 C was 93, 47, and 22% respectively. On the basis of these results, it can be expected that aerated sewage lagoons operating in the "mid-continental" climate of the Canadian prairie provinces would discharge at least 50% of incoming Na₃NTA for 6 months of the year.The presence of a bacterial predator, Daphnia, was found to enhance the breakdown of Na₃NTA.Fluctuations in Na₃NTA removal appeared to increase with decreasing model lagoon temperature.